Need Li item active

I need to keep active the li Item after the clicking on ul(id+ tree3).

 

Issue is when click on the ul and again click on ul then page is still opened the same but li is not remaining active. Please help

 

code is as given below:

 

 

My UI is as given below:

 

So while I am clicking on CDNA, the li will wrap and when clicking again then the segment will not remain active but it should remain active